Floating Locking Insert

ABSTRACT

An insert for receipt within a plate aperture having an inner wall along the plate aperture includes a body and collar. The body has inner and outer surfaces. The inner surface defines an insert aperture having a longitudinal axis. The collar extends from the outer surface in a first radial direction perpendicular to the longitudinal axis and extends along only a portion of the outer surface in a second radial direction transverse to the first radial direction and the longitudinal axis. The collar defines a first radial distance from the longitudinal axis at a first position of the collar and a second radial distance from the longitudinal axis at a second position of the collar that differs from the first radial distance. A fixation system includes the plate and insert which is receivable within the plate aperture such that the collar contacts and is slideable along the inner wall.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. patent applicationSer. No. 16/284,520, filed Feb. 25, 2019, which is a continuation ofU.S. patent application Ser. No. 15/073,235, filed Mar. 17, 2016, nowU.S. Pat. No. 10,251,685, the disclosures of which are herebyincorporated herein by reference.

FIELD OF THE INVENTION

The present invention relates generally to attachment devices forconnecting a plate to a support, such as a bone mass, and in particularrelates to such devices that use polyaxial locking fasteners forfixation.

BACKGROUND OF THE INVENTION

Plates for osteosynthesis or arthrodesis are often fixed to bonesubstantially parallel to a longitudinal bone axis using screws or otherfixation elements. Such plates are firmly fixed to a plurality of boneparts or fragments to prevent their movement relative to each other.

Spherical-head screws cooperating with radiused apertures in plates havebeen used to bring the plate into compression onto a bone until thefriction of the plate on the bone stabilizes the assembly. Theseassemblies allow screws to be implanted during a surgical operationwithin the plate aperture at multiple angles relative to the plate tocompress separated bone parts or fragments. The shortcoming of thesesystems is their low resistance to compression stresses exerted parallelto a plane generally defined by the plate.

A second generation of assembled screw-and-plate systems calledmonoaxial-locking and polyaxial-locking systems have relied on athreaded engagement of a screwhead with a plate aperture such that thestrength of the assembly no longer depends on the compression of theplate against the bone. These systems allow for the assembly to takeplace away from the bone section being repaired and, in some instances,the possibility of selecting an angle of screw implantation during anoperation while achieving strength sufficient for postoperativestresses.

Inserts have been added to monoaxial or polyaxial screw-and-platesystems in which the insert has a threaded engagement with any of theplate and the screw. In some such systems, a screw has been threadedinto an insert to lock the insert, by way of friction, to a plate at anangle corresponding to a desired angle of implantation for the screw. Toenhance the locking of these inserts, an outer surface of inserts hasbeen given radial offsets. Such offsets have extended along an entirearcuate surface within a plane through a longitudinal axis defined bythe inserts which creates friction that diminishes the control of theinsert when attempting to set the desired insertion angle.

Thus, there exists a need for a better way in which to align fastenersfor fixation within plates.

BRIEF SUMMARY OF THE INVENTION

In accordance with an aspect, an insert may include a body and a collar.The insert may be received within a plate aperture which may have aninner wall along at least a portion of the plate aperture.

The body may have inner and outer surfaces. The inner surface may definean insert aperture which may have a longitudinal axis. The collar mayextend from a portion of the outer surface of the body in a first radialdirection perpendicular to the longitudinal axis. The collar also mayextend along only a portion of the outer surface of the body in a secondradial direction transverse to the first radial direction and thelongitudinal axis. The collar may define a first radial distance fromthe longitudinal axis at a first position of the collar and a secondradial distance from the longitudinal axis at a second position of thecollar that differs from the first radial distance.

In some arrangements, the collar may be a plurality of collars.

In some arrangements, the collar may include a plurality of sections.The plurality of sections may be spaced apart around the circumferenceof the body.

In some arrangements, an outer edge of each of the sections may define arespective first radial distance from the longitudinal axis at a firstposition of the respective outer edge and a respective second radialdistance from the longitudinal axis at a second position of therespective outer edge that differs from the respective first radialdistance.

In some arrangements, each of the plurality of sections may includethree collar segments. An outer edge of a first collar segment may havea first radius along the outer edge of the first collar segment. A firstend of an outer edge of a second collar segment may intersect the outeredge of the first collar segment. The outer edge of the second collarsegment may have a second radius along the outer edge of the secondcollar segment. An outer edge of a third collar segment may intersect asecond end of the outer edge of the second collar segment opposite thefirst end of the outer edge of the second collar segment. The outer edgeof the third collar segment may have a third radius along the outer edgeof the third collar segment. The third radius may be greater than thesecond radius. The second radius may be greater than the first radius.

In some arrangements, the collar may define a substantially non-circularshape with rounded corners.

In some arrangements, the collar may have a maximum length defined by afirst linear distance in a direction perpendicular to the longitudinalaxis from the outer surface of the body to an edge of the collar. Thecollar also may have a maximum width defined by a second linear distancein a direction parallel to the longitudinal axis. The first lineardistance may be less than the second linear distance.

In some arrangements, the collar may have a maximum length defined by afirst linear distance in a direction perpendicular to the longitudinalaxis from the outer surface of the body to an edge of the collar. Thecollar also may have a maximum width defined by a second linear distancein a direction parallel to the longitudinal axis. The first lineardistance may be greater than the second linear distance.

In some arrangements, the collar may have opposing upper and lowerstopper surfaces. The upper and lower stopper surfaces may be configuredfor contacting corresponding upper and lower stopper surfaces of theplate.

In some arrangements, the upper and lower stopper surfaces of the collarmay intersect. In this manner, the upper and lower stopper surfaces maydefine an edge. The edge may be configured for contacting the innerwall.

In some arrangements, each of the upper and lower stopper surfaces ofthe collar may intersect an edge surface to define opposing upper andlower edges. The upper and lower edges may be configured for contactingthe inner wall.

In some arrangements, the edge surface may be concave.

In some arrangements, the insert aperture may be threaded for receipt ofa threaded fastener.

In some arrangements, the inner surface may include at least one reliefsection. Any of the relief sections may define a plurality of separatedthread sections.

In some arrangements, the body may include a slot that may extendthrough the inner and outer surfaces. The body may be compressiblebetween rest and compressed conditions such that the slot may have agreater width in the rest condition than the slot has in the compressedcondition.

In some arrangements, the body may include a plurality of notches thatmay extend into a thickness of the body defined by the inner and outersurfaces. The plurality of notches may be configured for receiving tinesof an instrument. At least first and second notches of the plurality ofnotches may be positioned on opposite sides of the slot and may bemoveable relative to each other. In this manner, when the first andsecond notches are moved in a direction toward each other, the body maybe compressed and the slot width may be become smaller.

In accordance with another aspect, a fixation system may include a plateand an insert. The plate may have at least one plate aperture which mayhave an inner wall along at least a portion of the plate aperture.

The insert may include a body and a collar. The body may have inner andouter surfaces. The inner surface may define an insert aperture whichmay have a longitudinal axis. The collar may extend from a portion ofthe outer surface of the body in a first radial direction perpendicularto the longitudinal axis. The collar also may extend along only aportion of the outer surface of the body in a second radial directiontransverse to the first radial direction and the longitudinal axis. Thecollar may define a first radial distance from the longitudinal axis ata first position of the collar and a second radial distance from thelongitudinal axis at a second position of the collar that differs fromthe first radial distance. The insert may be receivable within the plateaperture of the plate. In this manner, the collar may contact and may beslideable along the inner wall of the plate.

In some arrangements, the collar may be a plurality of collars.

In some arrangements, the inner wall may define a longitudinal axis. Theinsert may be rotatable about the longitudinal axis of the inner walland may be translatable along the longitudinal axis of the inner wall.

In accordance with another aspect, a fixation system may include a plateand an insert. The plate may have at least one plate aperture which mayhave an inner wall defining an inner wall longitudinal axis and may havea guidance surface that may extend from the inner wall. The inner wallmay define a wall aperture defined by a first radius, and the guidancesurface may be defined by a second radius smaller than the first radiusdefining the wall aperture.

The insert may be receivable in the inner wall of the plate and may berotatable about rotational axes perpendicular to the inner walllongitudinal axis. An outer surface of the insert may be curved suchthat the insert may be slideable along the guidance surface duringrotation of the insert about the rotational axes.

In some arrangements, the guidance surface may be a plurality ofguidance surfaces.

In some arrangements, the insert may define a longitudinal axis and mayinclude a collar. The collar may extend from a portion of the outersurface of the insert in a first radial direction perpendicular to theinsert longitudinal axis and may extend along only a portion of theouter surface of the insert in a second radial direction transverse tothe first radial direction and the insert longitudinal axis. The collarmay define a first radial distance from the insert longitudinal axis ata first position of the collar and a second radial distance from theinsert longitudinal axis at a second position of the collar that differsfrom the first radial distance. The collar may be slideable along theinner wall during rotation of the insert about the rotational axes.

In some arrangements, the collar may be a plurality of collars.

In accordance with another aspect, a fixation system may include a plateand an insert. The plate may have at least one plate aperture which mayhave an inner wall defining an inner wall longitudinal axis and may haveupper and lower plate end surfaces extending from the inner wall.

The insert may be receivable in the inner wall of the plate and may berotatable about rotational axes perpendicular to the inner walllongitudinal axis. The insert may define a longitudinal axis and mayinclude a collar. The collar may extend from a portion of the outersurface of the insert in a first radial direction perpendicular to theinsert longitudinal axis and may extend along only a portion of theouter surface of the insert in a second radial direction transverse tothe first radial direction and the insert longitudinal axis. The collarmay have opposing upper and lower stopper surfaces. In this manner, theupper plate end surface of the plate may prevent rotation of the upperstopper surface of the collar, and the lower plate end surface of theplate may prevent rotation of the lower stopper surface of the collar.

In accordance with another aspect, a plate may be fixed to a bone by aprocess. In particular, an insert may be received in a plate aperture ofa plate defining a plate longitudinal axis. The insert may include abody and a collar. The body may have inner and outer surfaces. The innersurface of the body may define a body aperture through the inner surfacedefining an insert longitudinal axis. The collar may extend from thebody in a first radial direction perpendicular to the insertlongitudinal axis and may extend along only a portion of the body in asecond radial direction transverse to the first radial direction and theinsert longitudinal axis. The collar may define a first radial distancefrom the insert longitudinal axis at a first position of the collar anda second radial distance from the insert longitudinal axis at a secondposition of the collar that differs from the first radial distance. Afastener may be threaded into the inner surface of the insert at apredetermined angle relative to the plate longitudinal axis. The insertmay be rotated to compress the insert to lock the fastener at thepredetermined angle.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective cross-sectional view of a fixation system inaccordance with an embodiment;

FIG. 2 is a plan view of a section of a plate and an insert of thefixation system of FIG. 1;

FIG. 3A is an elevation view of a cross-section taken at 3A-3A of aportion of the plate and the insert of FIG. 2;

FIG. 3B is an exploded view taken at region X of FIG. 3A;

FIG. 3C is an elevation view of a cross-section taken at 3C-3C of aportion of the plate and the insert of FIG. 2;

FIG. 3D is an exploded view taken at region Y of FIG. 3C;

FIG. 4 is a plan view of a cross-section taken at 4-4 of FIG. 3A;

FIG. 5 is an elevation cross-sectional view of portions of a plate andan insert in accordance with another embodiment; and

FIG. 6 is an elevation cross-sectional view of portions of a plate andan insert in accordance with another embodiment.

DETAILED DESCRIPTION

Referring now to the drawings, as shown in FIG. 1, fixation system 100generally includes plate 110, insert 140, and fastener 95. Plate 110 maybe but is not limited to being a bone fixation plate, such as may beused for the treatment of proximal humeral, radial, elbow, or claviclefractures. Plate 110 may be but is not limited to being made ofbiocompatible materials such as titanium and its alloys, cobalt and itsalloys including cobalt-chromium, and stainless steel. Insert 140 may bedimensioned and may be flexible such that the insert may be received forpolyaxial movement within and frictional locking with aperture 112 ofplate 110. Insert 140 may be but is not limited to being made ofbiocompatible materials such as titanium and its alloys, cobalt and itsalloys including cobalt-chromium, and stainless steel. Fastener 95 maybe a locking screw having a fully threaded shank 96, which may bereceived into a patient's bone or other tissue, as well as threaded head97 which may include bore 98 for receipt of a turning tool such as ahex-head or TORX screwdriver. As shown, head 97 of fastener 95 may betapered such that a perimeter of the head adjacent shank 96 may besmaller than a perimeter of the head surrounding bore 98.

As shown in FIG. 2, plate aperture 112 of plate 110 may pass through athickness of plate 110 and may be generally in a square form with theexception of two grooves 113A, 113B at opposing corners at a top end ofthe aperture. Upper chamfer 114 may extend around plate aperture 112 andbetween the plate aperture and top surface 115 of plate 110. Grooves113A, 113B and upper chamfer 114 ease the assembly of insert 140 intoplate 110.

As shown in FIGS. 3A-3D, plate aperture 112 may include inner wall 120as well as opposing upper and lower plate end surfaces 122, 123intersecting and extending transversely to opposing ends of inner wall120 to provide opposing abutments. As in the arrangement shown, innerwall 120, which may have a substantially smooth surface, may extendalong a majority of plate aperture 112. Inner wall 120 may have across-section defined by any given plane through a longitudinal axis ofaperture 112 that is substantially in the form of a truncated ellipse.Plate aperture 112 may include upper guidance surface 126 intersectingupper plate end surface 122 on one end and chamfer 114 on an oppositeend of the upper guidance surface to form an upper bearing surface forinsert 140 as well as lower guidance surface 127 intersecting lowerplate end surface 123 on one end and lower chamfer 116, which extends tobottom surface 125 of plate 110, on an opposite end to form a lowerbearing surface for insert 140.

As further shown, insert 140 may include a body or inner body 142 andcollar 162. Inner body 142 may include inner surface 144 and outersurface 146 separated by a thickness of the inner body. Inner and outersurfaces 144, 146 of insert 140 may extend between top surface 148 andbottom surface 149 of the inner body. As in the example shown, outersurface 146 may be substantially smooth and generally may be in the formof a truncated hollow ellipsoid such that cross-sections of the outersurface taken through the longitudinal axis of aperture 112 definetruncated ellipses. In the example shown, outer surface 146 is in theform of a truncated hollow sphere.

Inner surface 144 may include threads 145 extending along a majority ofthe length of the inner surface. Inner surface 144 may be tapered suchthat a portion of the inner surface intersecting top surface 148 mayhave a larger perimeter than a portion of the inner surface intersectingbottom surface 149. In this manner, inner surface 144 may be threadablyengaged with head 97 of fastener 95.

As best shown in FIG. 2, inner surface 144 may include first and secondrecesses 151, 152 situated generally opposite a slot defined by opposinginsert ends 153, 154 and extending through the thickness of inner body142 in which first recess 151 is closer to the slot. In this manner,insert 140 may be compressed from a rest condition in which the slot andthe insert have preset rest widths to a compressed condition in whichthe slot and the insert have widths smaller than their respective presetrest widths. As in the example shown, opposing insert ends 153, 154 ofinsert 140 may be aligned such that when insert 140 is compressedsufficiently, opposing insert ends 153, 154 may abut each other. Tofacilitate the compression of insert 140, inner body 142 may includenotches 156, 157 adjacent to insert ends 153, 154. Notches 156, 157 maybe dimensioned to receive tines of tongs, a snap ring insertion tool, orother suitable instrument which may be used to urge insert ends 153, 154toward each other to reduce the width of insert 140 for placement intoplate aperture 112 of plate 110.

Referring to FIGS. 2, 3A, and 3C, collar 162 extends along the entireperimeter of outer surface 146 of inner body 142 and covers a generallycentral portion of the outer surface of the inner body. Duringcompression of insert 140 such that opposing insert ends 153, 154 arebrought closer together, a section of collar 162 adjacent to the slotdefined by insert ends 153, 154 may be generally the shortest distancefrom a longitudinal axis through a centroid of the insert relative tothe rest of the collar. As such, plate aperture 112 and plate grooves113A, 113B may be dimensioned such that collar 162 and thus insert 140must be oriented such that the slot defined by insert ends 153, 154 iswithin a region of plate 110 between plate grooves 113A, 113B duringinsertion of the insert into the plate. Likewise, once insert 140 isplaced within plate 110, the insert may be removed only when the insertis oriented about the longitudinal axis of aperture 112 in which theslot defined by insert ends 153, 154 is situated between plate grooves113A, 113B.

As shown in FIGS. 3A-3D, collar 162 includes opposing upper stoppersurface 163 and lower stopper surface 164. Upper and lower stoppersurfaces 163, 164 extend from inner body 142 such that, during rotationof insert 140 within a plane passing through the longitudinal axis ofplate aperture 112, i.e., during vertical rotation of the insert, whenthe insert is within the plate, the upper and lower stopper surfaces mayabut either or both of corresponding upper and lower plate end surfaces122, 123. In this manner, upper and lower plate end surfaces 122, 123restrict vertical rotation of the insert within the plate and aid inpreventing disassembly of the insert from the plate. As in the exampleshown, the entirety of insert 140 may be moveable in a verticaldirection along the longitudinal axis of plate aperture 112 when upperand lower stopper surfaces 163, 164 are between upper and lower plateend surfaces 122, 123. Upper and lower plate end surfaces 122, 123 arelocated along plate aperture 112 such that insert 140 may be rotatableup to 15 degrees in clockwise and counterclockwise directions in whichmaximum travel is possible when collar 162 is centered in the verticaldirection along inner wall 120 of plate 110.

Upper and lower stopper surfaces 163, 164 may intersect to define edge165. When insert 140 is oriented in plate 110 such that the slot definedby insert ends 153, 154 of insert 140 is situated between plate grooves113A, 113B as illustrated in FIG. 2, edge 165 may be in contact withinner wall 120 in the cross-section shown in FIG. 3A and may be incontact with only one side of the inner wall in the cross-section shownin FIG. 3C.

Still referring to FIGS. 3A-3D, when the slot defined by insert ends153, 154 of insert 140 is situated between plate grooves 113A, 113B asillustrated in FIG. 2, radii defining the cross-section of outer surface146 of inner body 142 shown in FIG. 3A may be different than radiidefining the cross-section of inner wall 120 such that the cross-sectionof outer surface 146 shown curves away from the cross-section of innerwall 120 shown and inwardly towards the longitudinal axis of aperture112 of plate 110. As such, portions of outer surface 146 nearest top andbottom surfaces 148, 149 of inner body 142 in the cross-section shown inFIG. 3A are further from inner wall 120 than portions of outer surface146 further away from the top and bottom surfaces of the inner body inthe cross-section shown in FIG. 3A. In contrast, when insert 140 is inthis same orientation, radii defining the cross-section of outer surface146 of inner body 142 shown in FIG. 3C may be different than radiidefining the cross-section of inner wall 120 such that the cross-sectionof outer surface 146 shown curves only slightly inwardly towards thelongitudinal axis of aperture 112 of plate 110. As such, portions ofouter surface 146 nearest top and bottom surfaces 148, 149 of inner body142 in the cross-section shown in FIG. 3C are further from inner wall120 than portions of outer surface 146 further away from the top andbottom surfaces of the inner body in the cross-section shown in FIG. 3C.

When insert 140 is in the orientation shown in FIGS. 3A-3D, thecross-section of outer surface 146 shown in FIG. 3C near theintersections of the outer surface with each of top and bottom surfaces148, 149 may abut the respective upper and lower guidance surfaces 126,127 of plate aperture 112 of plate 110 on the side opposite where edge165 of the insert contacts inner wall 120 in the cross-section shown inFIG. 3C. Similarly, the cross-section of outer surface 146 shown in FIG.3C near the intersection of the outer surface with the top surface 148may abut the upper guidance surface 126 of aperture 112 of plate 110 onthe same side that edge 165 of the insert contacts inner wall 120 in thecross-section shown in FIG. 3C. As demonstrated by the imaginary line ofcontact 199 shown in FIG. 3D, upon rotation of insert 140 from theorientation of the insert shown in FIGS. 3A-3D within a plane passingthrough the longitudinal axis of plate aperture 112, the cross-sectionof outer surface 146 on the same side which edge 165 contacts inner wall120 will contact lower guidance surface 127. In this manner, outersurface 146 and thus insert 140 is further guided by upper and lowerguidance surfaces 126, 127 of plate 110 during such rotation.

As in the example of FIGS. 3A-3D, contact between upper and lowerguidance surfaces 126, 127 of plate aperture 112 of plate 110 and outersurface 146 of insert 140 may be substantially a point contact.Similarly, contact between inner wall 120 and edge 165 of collar 162 ofinsert 140 may be substantially a point or line contact. In this manner,friction between plate 110 and insert 140 may be minimized duringrotation of the insert about the longitudinal axis of plate aperture 112of the plate and during rotation of the insert within planes passingthrough the longitudinal axis of aperture 112.

Referring now to FIG. 4, along a central section of plate aperture 112of plate 110, inner wall 120 of the plate aperture may be in the form ofa square having rounded corners 128. Likewise, along a central sectionof insert 140, the insert may be substantially in the form of a squarehaving collar sections 166 in the form of rounded corners defined byedge 165 of collar 162 in which the rounded corners of the insertgenerally correspond to the rounded corners of the plate when the insertis placed into the plate. As shown, one of collar sections 166 of collar162 may be divided by the slot defined by insert ends 153, 154. Each ofcollar sections 166 may be separated by recesses 167 of collar 162which, when insert 140 is fully inserted into plate 110, do not contactaperture 112 of the plate. In this manner, when fastener 95 is inserted,such as by threading, into insert 140, the interface of collar sections166 of the insert with respective rounded corners 128 may providefixation of the insert to the plate and thus fixation of the fastenerrelative to the plate. Collar recesses 167 may also provide for greaterflexibility of insert 140 due to the decrease in thickness of the insertat the locations of these recesses.

Each of collar sections 166 of collar 162 of insert 140 may include aplurality of collar segments, such as first collar segment 168A, secondcollar segment 168B having an end intersecting an end of the firstcollar segment, and third collar segment 168C intersecting an end of thesecond collar segment opposite the end of the second collar segment 168Bintersecting the first collar segment. As demonstrated in the exampleshown in FIG. 4, the points along the length of first collar segment168A may be set at a distance from a longitudinal axis of insert 140that is less than the distance that the points along the length ofcollar segment 168B are set at a distance from the longitudinal axis ofthe insert, and the points along the length of collar segment 168B maybe set at a distance from the longitudinal axis of the insert that isless than the distance that the points along the length of collarsegment 168C are set at a distance from the longitudinal axis of theinsert. In this manner, upon insertion of insert 140 into plate aperture112 of plate 110 and engagement of head 97 of fastener 95 with innersurface 144 of insert 140, rotation of insert 140 about the longitudinalaxis of plate 140 in a clockwise direction may produce an increasingamount of friction between collar 162 of the insert and inner wall 120of the plate until the insert becomes locked in position within theplate aperture. In the example shown, collar 162 of insert 140 may bemade of a material that is as hard or harder than the material ofaperture 112 of plate 110 such that the collar does not deform uponlocking within the plate aperture. In arrangements in which aperture 112of plate 110 has a similar hardness collar 162 of insert 140, plateaperture 112 also may not deform during vertical movement of collar 162along the plate aperture. In other such arrangements, collar 162 ofinsert 140 may be made of a harder material than aperture 112 of plate110 such that the collar may carve or otherwise deform the plate tocreate rigid fixation between the insert and the plate. In such otherarrangements, the section of collar 162 adjacent to the slot defined byinsert ends 153, 154 may be generally the shortest distance from thelongitudinal axis through the centroid of the insert relative to therest of the collar.

In some arrangements, head 97 of fastener 95 may be locked with insert140 at the same time the insert is locked with plate aperture 112, or asin the example shown, continued rotation of the fastener may lock thefastener head. In the example shown, head 97 of fastener 95 may beinserted into inner surface 144 of insert 140, and shank 96 of fastener95 may be inserted into a bone, at a predetermined angle relative to thelongitudinal axis of aperture 112 of plate 110. In this manner, uponlocking of insert 140 within plate aperture 112 and locking of fastener95 with inner surface 144 of the insert, the insert and the fastener maybe locked at the predetermined angle relative to the longitudinal axisof the plate aperture of plate 110.

During a surgical operation, a physician, or other qualified medicalprofessional, may determine that a set of bone fragments or bone partsrequire repair by way of an osteosynthesis or arthrodesis procedureusing plate 110. Plate 110 may be placed onto each of the bone fragmentsor bone parts such that at least one plate aperture 112 lies on each ofthe bone fragments or bone parts. Insert 140 may be inserted into innerwall 120 of a plate aperture 112 selected by the medical professional.The medical professional may determine an appropriate insertion anglefor insertion of fastener 95 into a bone fragment or bone part toachieve sufficient, and preferably optimal, postoperative stresses.Shank 96 of fastener 95 may be inserted through inner surface 144 ofinsert 140 to orient the insert. Fastener shank 96 then may be threaded,such as by a TORX or a hex head screwdriver, into the bone fragment orbone part at the predetermined insertion angle. As fastener shank 96 isthreaded further into the bone fragment or bone part, fastener head 97may be threaded into threads 145 of inner surface 144 of insert 140causing rotation of the insert within plate 110 until the insert becomeslocked within plate aperture 112. In this manner, fastener 95 may belocked with insert 140 and locked relative to plate aperture 112 ofplate 110, at the predetermined angle. If the medical professional isunsatisfied with the insertion angle of fastener 95, fastener 95 may beunthreaded from the bone fragment or bone part, preferably prior tothreading of head 97 with insert 140, and a new insertion angle for thefastener may be selected. Fastener 95 then may be inserted into the bonefragment or bone part at the newly selected orientation and lockedrelative to plate 110 as described previously herein.

As shown in FIG. 5, in an alternative arrangement, fixation system 200may be the same as fixation system 100 with the exception that fixationsystem 200 may include plate 210 including plate aperture 212 havinginner wall 220 in place of plate aperture 112 and inner wall 120,respectively, of plate 110 and insert 240 having collar 262 in place ofcollar 162 of insert 140. Insert 240 may be the same as insert 140 withthe exception that at least collar 262 of insert 240, and in somearrangements all of insert 240, is made of a softer material than plate210. For example, insert 240 may be made of but is not limited to beingmade of any of cobalt-chromium alloys, titanium alloys, steel and itsalloys, medical grade polymers, and ceramic when plate 210 is made of arelatively harder material. As such, vertical movement of collar 262against inner wall 220 deforms the inner wall. In this manner, insert240 is maintained in plate aperture 212 by both the deformed surface ofinner wall 220 and the compression of the insert against the inner wallupon receipt of a fastener into the insert.

As shown in FIG. 6, in an alternative arrangement, fixation system 300may be the same as fixation system 100 with the exception that fixationsystem 300 may include insert 340 having collar 362 in place of collar162 of insert 140. Collar 362 may be the same as collar 162 with theexception that collar 362 may include upper and lower stopper surfaces363, 364 in place of upper and lower stopper surfaces 163, 164 and mayinclude edge surface 365 which intersects upper and lower stoppersurfaces 363, 364 to define edges 358, 359. As shown, edge surface 365may be concave such that upper edge 358 and lower edge 359 contact innerwall 120 of plate 110 during rotation and vertical movement of insert340 within plate aperture 112.

In some alternative arrangements, the relative distances of any of thecollar segments may be in any mixed order and, in some arrangements, maybe the same distance such that there are only two segments in any collarsection of an insert. In some alternative arrangements, the plateaperture and the insert may be in different corresponding non-circularforms at their central cross-sections along the longitudinal axis, suchas but not limited to a triangular or an elliptical form, rather than inthe square forms of plate 110 and insert 140.

It is to be understood that the disclosure set forth herein includes allpossible combinations of the particular features set forth above,whether specifically disclosed herein or not. For example, where aparticular feature is disclosed in the context of a particular aspect,arrangement, configuration, or embodiment, that feature can also beused, to the extent possible, in combination with and/or in the contextof other particular aspects, arrangements, configurations, andembodiments of the invention, and in the invention generally.

Furthermore, although the embodiments disclosed herein have beendescribed with reference to particular features, it is to be understoodthat these features are merely illustrative of the principles andapplications of the present invention. It is therefore to be understoodthat numerous modifications, including changes in the sizes of thevarious features described herein, may be made to the illustrativeembodiments and that other arrangements may be devised without departingfrom the spirit and scope of the present invention. In this regard, thepresent invention encompasses numerous additional features in additionto those specific features set forth in the claims below. Moreover, theforegoing disclosure should be taken by way of illustration rather thanby way of limitation as the present invention is defined by the claimsset forth below.

1. An insert configured for receipt within a plate aperture and forreceiving a fastener, comprising: an outer surface including a sidesurface, a top surface extending from a first end of the side surface,and a bottom surface extending from a second end of the side surfaceopposite the first end of the side surface; and an inner surfaceextending from the top surface to the bottom surface of the outersurface and defining an insert aperture defining an insert longitudinalaxis, the inner surface including a first unthreaded section and firstand second threaded sections, each of the unthreaded and the threadedsections having portions extending along a perimeter of the innersurface, at least a portion of the first unthreaded section beingbetween the first and the second threaded sections within a first planeorthogonal to the insert longitudinal axis.
 2. The insert of claim 1,wherein the first unthreaded section extends through at least the bottomsurface of the outer surface.
 3. The insert of claim 2, wherein theinner surface includes threads extending between the top surface of theouter surface and the first unthreaded section.
 4. The insert of claim1, wherein the inner surface includes a second unthreaded section and athird threaded section, the second unthreaded section being between thesecond and the third threaded sections within the first plane.
 5. Theinsert of claim 4, wherein the first unthreaded section is recessed fromeach of the first and the second threaded sections and the secondunthreaded section is recessed from each of the second and the thirdthreaded sections.
 6. The insert of claim 5, wherein the first and thesecond unthreaded sections are recessed such that the inner surface isscalloped.
 7. The insert of claim 4, further comprising a slot extendingfrom the inner surface to the outer surface and defining opposing endsof the first threaded section and the third threaded section,respectively, the insert thereby being compressible between rest andcompressed conditions such that the slot has a greater width in the restcondition than the slot has in the compressed condition.
 8. The insertof claim 7, wherein the slot defines a slot plane parallel to thelongitudinal axis in the rest condition.
 9. The insert of claim 7,further comprising spaced apart notches extending from the inner surfaceto the outer surface, one of the notches extending into the firstthreaded section and another one of the notches extending into the thirdthreaded section.
 10. The insert of claim 1, wherein the outer surfacehas a non-circular outer perimeter within the first plane.
 11. Theinsert of claim 10, further comprising a main body and a collarextending radially from the main body, the main body and the collartogether defining the outer surface, wherein the outer perimeter of theouter surface in the first plane is defined by the collar.
 12. Afixation system comprising: a plate having an inner wall defining aplate aperture and an inner wall longitudinal axis; and the insert ofclaim 1, the insert being receivable within the plate aperture such thatthe insert is rotatable within the inner wall.
 13. The fixation systemof claim 12, further comprising one or more fasteners including a firstfastener, wherein the insert when received in the plate aperture isrotatable about rotational axes defined by the insert that areperpendicular to the inner wall longitudinal axis, and wherein the firstfastener is rotatable within and thereby configured for threadedengagement with the first and the second threaded sections of the insertto lock the fastener to the insert and to lock the outer surface of theinsert to the inner wall of the plate and thereby lock the fastener suchthat a fastener longitudinal axis defined by the fastener is at a firstangle relative to the inner wall longitudinal axis.
 14. The fixationsystem of claim 13, wherein the insert is slideable along the inner walllongitudinal axis when the insert is received in the plate aperture. 15.The fixation system of claim 13, wherein the insert is rotatable withinthe inner wall of the plate and the first fastener is configured forthreaded engagement with the first and the second threaded sections ofthe insert to lock the outer surface of the insert to the inner wall ofthe plate such that the insert longitudinal axis and the fastenerlongitudinal axis are transverse to the inner wall longitudinal axis.16. An insert configured for receipt within a plate aperture and forreceiving a fastener, comprising: an outer surface including a sidesurface, a top surface extending from a first end of the side surface,and a bottom surface extending from a second end of the side surfaceopposite the first end of the side surface; and an inner surfaceextending from the top surface to the bottom surface of the outersurface and defining an insert aperture defining an insert longitudinalaxis, the inner surface including first unthreaded and first threadedsections having portions extending within a first plane orthogonal tothe insert longitudinal axis, the first threaded section tapering alonga portion of the inner surface relative to the insert longitudinal axis.17. The insert of claim 16, wherein the fastener has a head and a shankextending from the head, the inner surface further including a secondunthreaded section and second and third threaded sections, each of thesecond unthreaded section and the second and the third threaded sectionshaving portions extending along a perimeter of the inner surface, thefirst and the second threaded sections being separated by the firstunthreaded section within the first plane and the second and the thirdthreaded sections being separated by the second unthreaded sectionwithin the first plane, the second and the third threaded sectionstapering along additional portions of the inner surface relative to theinsert longitudinal axis such that the first, the second, and the thirdthreaded sections are configured for simultaneous threaded engagementwith the head of the fastener.
 18. The insert of claim 17, wherein thefirst and the second threaded sections are joined by a fourth threadedsection continuous with the first and the second threaded sections, andwherein the second and the third threaded sections are joined by a fifththreaded section continuous with the second and the third threadedsections.
 19. The insert of claim 17, further comprising a slotextending from the inner surface to the outer surface and definingopposing ends of the first threaded section and the third threadedsection, respectively, the insert thereby being compressible betweenrest and compressed conditions such that the slot has a greater width inthe rest condition than the slot has in the compressed condition.
 20. Aninsert configured for receipt within a plate aperture and for receivinga fastener, comprising: an outer surface including a side surface, a topsurface extending from a first end of the side surface, and a bottomsurface extending from a second end of the side surface opposite thefirst end of the side surface; and an inner surface extending from thetop surface to the bottom surface of the outer surface and defining aninsert aperture defining an insert longitudinal axis, the inner surfaceincluding a first unthreaded section and first and second threadedsections, each of the unthreaded and the threaded sections havingportions extending along a perimeter of the inner surface, at least aportion of the first unthreaded section being between the first and thesecond threaded sections within a first plane orthogonal to the insertlongitudinal axis, and each of the first and the second threadedsections extending within the first plane and tapering along portions ofthe inner surface relative to the insert longitudinal axis, wherein theside surface of the outer surface is partially defined by a collarextending from a base portion of the side surface in a first radialdirection within the first plane, the collar being opposite, in a radialdirection, at least the first and the second threaded sections.